Surgical instrument and bushing

ABSTRACT

A surgical instrument comprising a handle assembly, and actuation member, an elongated body portion, and a locking mechanism is disclosed. The locking mechanism is disposed in mechanical cooperation with the actuation member, and is configured to substantially prevent at least a partial movement of the actuation member when the elongated body portion is not engaged with a loading unit. The locking mechanism comprises a link, a bushing, and a connecting member. The link is configured for mechanical engagement with a portion of a loading unit. At least a portion of the busing is disposed proximally of at least a portion of the link. At least a portion of the connecting member is disposed proximally of at least a portion of the bushing. Engagement between a loading unit and the elongated body portion causes proximal movement of the link, the bushing, and the connecting member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/666,022, filed Jun. 29, 2012 the entiredisclosure of which incorporated by reference herein.

BACKGROUND

1. Technical Field

This application relates to a surgical instrument, and moreparticularly, to an endoscopic surgical fastening instrument having aloading unit for applying a plurality of surgical fasteners to bodytissue, and to a bushing for use with the surgical instrument.

2. Background of Related Art

Various types of surgical instruments used to surgically join tissue areknown in the art, and are commonly used, for example, for closure oftissue or organs in transection, resection, anastomoses, for occlusionof organs in thoracic and abdominal procedures, and forelectrosurgically fusing or sealing tissue.

One example of such a surgical instrument is a surgical staplinginstrument, which may include an anvil assembly, a cartridge assemblyfor supporting an array of surgical staples, an approximation mechanismfor approximating the cartridge and anvil assemblies, and a firingmechanism for ejecting the surgical staples from the cartridge assembly.

Using a surgical stapling instrument, it is common for a surgeon toapproximate the anvil and cartridge members. Next, the surgeon can firethe instrument to emplace staples in tissue. Additionally, the surgeonmay use the same instrument or a separate instrument to cut the tissueadjacent or between the row(s) of staples.

SUMMARY

The present disclosure relates to a surgical instrument comprising ahandle assembly, and actuation member, an elongated body portion, and alocking mechanism. The locking mechanism is disposed in mechanicalcooperation with the actuation member, and is configured tosubstantially prevent at least a partial movement of the actuationmember when the elongated body portion is not engaged with a loadingunit. The locking mechanism comprises a link, a bushing, and aconnecting member. The link is disposed at least partially within theelongated body portion and is configured for mechanical engagement witha portion of a loading unit. At least a portion of the busing isdisposed proximally of at least a portion of the link. At least aportion of the connecting member is disposed proximally of at least aportion of the bushing, and the connecting member is disposed inmechanical cooperation with the actuation member. Engagement between aloading unit and the elongated body portion causes proximal movement ofthe link, the bushing, and the connecting member.

In disclosed embodiments, a distal face of the bushing abuts a proximalend of the link.

In disclosed embodiments, a proximal face of the bushing abuts a distalend of the connecting member.

In disclosed embodiments, the surgical instrument further comprises acontrol rod disposed at least partially within the elongated bodyportion, such that longitudinal translation of the control rod effects afunction of a loading unit when the loading unit is engaged with theelongated body portion. Here, control rod is longitudinally translatablewith respect to the link, with respect to the bushing and with respectto the connecting member. It is also disclosed that the control rod islongitudinally translatable through an aperture in the bushing. It isfurther disclosed that the control rod is longitudinally translatablethrough the connecting member.

In disclosed embodiments, a transverse dimension of a contacting portionof a proximal surface of the bushing is between about 2 to about 10times larger than a distal end of a wall of the connecting tube. It isalso disclosed that a transverse dimension of a contacting portion of adistal surface of the bushing is between about 1 to about 6 times largerthan a proximal end of the link.

The present disclosure also relates to a surgical instrument comprisinga handle assembly, and actuation member, an elongated body portion, aloading unit, and a locking mechanism. The actuation member is disposedin mechanical cooperation with the handle assembly. The elongated bodyportion extends distally from the handle assembly and defines alongitudinal axis. The loading unit includes a proximal body portion anda tool assembly. The proximal body portion is configured for selectiveengagement with the elongated body portion. The locking mechanism isdisposed in mechanical cooperation with the actuation member. Thelocking mechanism is configured to enable movement of the actuationmember when the elongated body portion and the loading unit are engaged.The locking mechanism comprises a link, a bushing, and a connectingmember. The link is disposed at least partially within the elongatedbody portion and is configured for mechanical engagement with a portionof the loading unit. At least a portion of the link is longitudinallytranslatable with respect to the elongated body portion. At least aportion of the busing is disposed proximally of at least a portion ofthe link. At least a portion of the bushing is longitudinallytranslatable with respect to the elongated body portion. At least aportion of the connecting member is disposed proximally of at least aportion of the bushing. The connecting member is disposed in mechanicalcooperation with the actuation member. Engagement between the loadingunit and the elongated body portion causes proximal movement of thelink, proximal movement of the bushing, and proximal movement of theconnecting member.

In disclosed embodiments, a distal face of the bushing abuts a proximalend of the link.

In disclosed embodiments, a proximal face of the bushing abuts a distalend of the connecting member.

In disclosed embodiments, the surgical instrument further comprises acontrol rod disposed at least partially within the elongated bodyportion, such that longitudinal translation of the control rod effects afunction of the loading unit when the loading unit is engaged with theelongated body portion. Here, it is disclosed that the control rod islongitudinally translatable with respect to the link, with respect tothe bushing and with respect to the connecting member. It is alsodisclosed that the control rod is longitudinally translatable through anaperture in the bushing. It is further disclosed that the control rod islongitudinally translatable through the connecting member.

In disclosed embodiments, a transverse dimension of a contacting portionof a proximal surface of the bushing is between about 2 to about 10times larger than a distal end of a wall of the connecting tube. It isalso disclosed that a transverse dimension of a contacting portion of adistal surface of the bushing is between about 1 to about 6 times largerthan a proximal end of the link.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described herein withreference to the drawings wherein:

FIG. 1 is a front, perspective view of one embodiment of the presentlydisclosed surgical instrument including a loading unit engaged with anelongated body;

FIG. 2 is a perspective view of the surgical instrument without theloading unit engaged with the elongated body;

FIG. 3 is a perspective view of the loading unit;

FIG. 4 is a perspective view of a locking mechanism of the surgicalinstrument;

FIG. 5 is a perspective view of a portion of the locking mechanism ofFIG. 4;

FIG. 6 is a longitudinal cross-sectional view of a portion of thesurgical instrument;

FIG. 7 is a perspective view of the elongated body portion of thesurgical instrument shown with parts separated;

FIG. 8 is a perspective view of a bushing shown in FIG. 7;

FIG. 9 is a cut-away perspective view of the locking mechanism takenalong line 9-9 of FIG. 4;

FIG. 10 is an enlarged view of the indicated area of detail shown inFIG. 9; and

FIG. 11 is a longitudinal cross-sectional view of a portion of thelocking mechanism.

DETAILED DESCRIPTION

Embodiments of the presently disclosed surgical instrument, and bushingfor use therewith, are described in detail with reference to thedrawings, wherein like reference numerals designate correspondingelements in each of the several views. As is common in the art, the term“proximal” refers to that part or component closer to the user oroperator, e.g., surgeon or physician, while the term “distal” refers tothat part or component farther away from the user.

A surgical stapling instrument of the present disclosure is indicated asreference numeral 10 in FIG. 1. The depicted surgical instrument firesstaples, but it may be adapted to fire any other suitable fastener suchas clips and two-part fasteners. Additionally, while the figures depicta linear fastener-applying surgical instrument, other types ofendoscopic surgical instruments are encompassed by the presentdisclosure and are usable with the disclosed bushing 100. For example,further details of endoscopic forceps are described in commonly-ownedU.S. Patent Publication No. 2010/0179540 to Marczyk et al., and U.S.patent application Ser. No. 12/718,143 to Marczyk et al., the entirecontents of each of which are hereby incorporated by reference herein.In another example, further details of a circular fastener-applyingsurgical instrument are described in commonly-owned U.S. PatentPublication No. 2009/0173767 to Milliman et al., the entire contents ofwhich are hereby incorporated by reference herein.

Generally, surgical instrument 10 includes a handle assembly 20including a movable handle 22, an elongated or endoscopic portion 30extending distally from the handle assembly 20 and defining alongitudinal axis “A,” and a loading unit 500 attachable to endoscopicportion 30, e.g., to allow surgical instrument 10 to have greaterversatility. Loading unit 500 includes a proximal portion 41 and an endeffector 40, including a cartridge 50 and an anvil 60, disposed adjacentthe proximal portion 41. The loading unit 500 may be configured for asingle use, and/or may be configured to be used more than once. Examplesof loading units for use with a surgical stapling instrument aredisclosed in commonly-owned U.S. Pat. No. 5,752,644 to Bolanos et al.,the entire contents of which are hereby incorporated by referenceherein.

The movable handle 22 is actuatable (e.g., through successive strokes)to cause distal advancement of a drive rod or control rod 52, such thatthe drive rod engages a portion of a drive assembly, which forces atleast a portion of the drive assembly to translate distally. (Furtherdetails of how actuation of movable handle 22 causes distal advancementof the drive rod are explained in U.S. Pat. No. 6,953,139 to Milliman etal., which is hereby incorporated by reference herein.) Distal movementof the drive rod, and in particular, a dynamic clamping member engagedtherewith, causes an actuation sled to move distally through thecartridge 50, which causes cam wedges of the actuation sled tosequentially engage pushers to move pushers vertically within retentionslots and eject fasteners towards the anvil 60. Subsequent to theejection of fasteners from the retention slots (and into tissue), acutting edge of the dynamic clamping member severs the fastened tissueas the cutting edge travels distally through a slot of the cartridge 50.

With reference to FIGS. 4-11, instrument 10 also includes a lockingmechanism 400 for preventing operation of instrument 10 before a loadingunit 500 has been engaged with elongated portion 30 of instrument 10.Locking mechanism 400 includes a first link 402, a spacer 404, a bushing460, a connecting member or connecting tube 406, and an articulationlocking member 408. First link 402 includes a plate-like member which issupported between control rod 52 and an inner body portion 232 ofelongated portion 30 of the instrument 10 on a flat surface 53 which isground into control rod 52 (see FIG. 10). Prior to attachment of loadingunit 500 to elongated portion 30, a distal end 402 a (FIG. 10) of firstlink 402 is positioned to engage the proximal end of loading unit 500when a loading unit 500 is engaged with elongated portion 30. First link402 includes a hole 414 (FIG. 7) which is dimensioned to receive aprotrusion 416 (FIG. 10) formed on spacer 404. Spacer 404 fits betweenfirst link 402 and an inner surface of outer tube 230 with a slightinterference. Spacer 404, link 402, and flat surface 53 on control rod52 function together to prevent control rod 52 from rotating in outertube 230. This ensures proper rotational alignment between a hook 242within outer tube 230 and a notch 248 in control rod 52.

Bushing 460 is disposed proximally of spacer 404 and is radiallypositioned between outer tube 230 and release link 202. Additionally,bushing 460 includes an aperture 462 extending longitudinallytherethrough. Aperture 462 is dimensioned and configured to allow aportion of control rod 52 to longitudinally slide therethrough. That is,bushing 460 is slidingly positioned about control rod 52.

The proximal end 402 b of first link 402 is configured to contact (i.e.,abuts or is axially movable into contact with) a distal surface 464 ofbushing 460. A proximal surface 466 of bushing 460 is configured tocontact (i.e., abuts or is axially movable into contact with) the distalend of connecting tube 406. Accordingly, proximal movement of first link402 causes corresponding proximal movement of bushing 460 and connectingtube 406, during loading of loading unit 500, for example. Similarly,distal movement of connecting tube 406 causes corresponding distalmovement of bushing 460 and first link 402, during firing of theinstrument, for example.

Additionally, the transverse dimension (i.e., along the y-axis in FIG.8) of a contacting portion of the proximal surface 466 of bushing 460(i.e., the portion of bushing 460 illustrated above control rod 52 inFIG. 10) is between about 2 to about 10 times larger than the distal end406 b of a wall of connecting tube 406, and the transverse dimension(i.e., along the y-axis in FIG. 8) of a contacting portion of the distalsurface 464 of bushing 460 is between about 1 to about 6 times largerthan the proximal end 402 b of first link 402. Thus, as can beappreciated, bushing 460 provides a robust engagement between first link402 and connecting tube 406. It is further envisioned that a surgicalinstrument without bushing 460 can be modified (e.g., by shortening thelength of first link 402 (e.g., adjacent its proximal end 402 b) and/orby shortening the length of connecting tube 406 (e.g., adjacent itsdistal end 406 b)) to accommodate the disclosed bushing 460.

Connecting tube 406 is slidably positioned about control rod 52 and hasa proximal end 406 a which abuts a distal face 408 a of locking member408 (FIG. 6). Locking member 408 is also slidably positioned aboutcontrol rod 52. When bushing 460 and connecting tube 406 are movedproximally by first link 402 (e.g., when loading unit 500 is beingloaded), locking member 408 is also moved proximally to allow distaltranslation of control rod 52. Further details of features and theoperation of related surgical instruments are disclosed incommonly-owned U.S. patent application Ser. No. 13/274,497 filed on Oct.17, 2011, the entire contents of which are hereby incorporated byreference herein.

With reference to FIG. 6, articulation mechanism 300 is illustrated andis configured to articulate an articulatable loading unit. Althoughloading unit 500 (FIG. 1) is not shown including articulation features,it is envisioned that loading unit 500 is articulatable in response torotation of an articulation lever 16. Alternatively, instrument 10 maybe configured as a cross-compatible device that is usable witharticulating loading units as well as non-articulating loading units.When used with a non-articulating loading unit, articulation assembly300 would simply be inoperable.

Articulation mechanism 300 includes articulation lever 16, a mechanismcover 320, biasing members 322, an upper clutch 324, a lower clutch 326,a main shaft 328, and a translation member 330. Lower clutch 326 isrotatably fixed and defines a central throughbore which is dimensionedto receive main shaft 328. Upper clutch 324 is rotatably fixed to mainshaft 328 and includes a plurality of spaced projections which arereceived within serrations of lower clutch 326. Biasing members 322 urgeupper clutch 324 into engagement with lower clutch 326 to releasablysecure articulation mechanism 300 in a fixed position and, thus, toreleasably secure the articulatable loading unit at a fixed angle ofarticulation.

Main shaft 328 includes a cam member 364, which is configured forsliding reception within a cam slot of translation member 330. Whenarticulation lever 16 is rotated, cam member 364 is rotated about anaxis defined by main shaft 328. When cam member 364 is driven inrotation, translation member 330 is urged to move linearly. Translationmember 330 is configured to engage an articulation link 333 (FIG. 7) ofan articulatable loading unit such that linear movement of translationmember 330 effects linear movement of the articulation link 333 toeffect articulation of the articulatable loading unit.

Referring to FIGS. 7 and 10, elongated body portion 30 of instrument 10includes an outer tube 230 and an inner body portion 232 through whichcontrol rod 52 is inserted. Inner body 232 defines a recess 236 (FIG.10) for slidably receiving release link 202 such that release link isslidably positioned between outer tube 230 and inner body portion 232. Aprojection 238 extending radially outwardly from body 232 extends intorectangular opening 222 of transverse extension 218 of release link 202(FIG. 7). A spring 240 is positioned within rectangular opening 222between projection 238 and a distal end of opening 222 to urge releaselink 202 distally.

Hook 242 is positioned between outer tube 230 and inner body portion 232adjacent a ramped cam surface 220. Hook 242 includes an elongated body244 having a transverse distal end 246. Transverse distal end 246 ispositioned adjacent a cutout 248 in control rod 52. Hook 242 is urged bya biasing member 250 to a position in which distal end 246 of hook 242is located externally of cutout 248. When release link 202 is movedproximally against the urging of biasing member 240 (e.g., by pulling arelease button 204 (FIGS. 1 and 2) proximally), cam surface 220 movesdistal end 246 of hook 242 into cutout 248 of control rod 52. If controlrod 52 is not in its retracted position shown in FIG. 10 and notch 248is not positioned to receive distal end 246 of hook 242, cam surface 220will not be able to cause hook 242 to move radially inwardly and thuslink 202 will not be able to move proximally. Thus, a loading unit 500cannot be removed or installed if control rod 52 is not in the retractedposition.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same. While several embodiments of the disclosure have been shownin the drawings, it is not intended that the disclosure be limitedthereto, as it is intended that the disclosure be as broad in scope asthe art will allow and that the specification be read likewise.Therefore, the above description should not be construed as limiting,but merely as exemplifications of particular embodiments. Those skilledin the art will envision other modifications within the scope and spiritof the claims appended hereto.

What is claimed is:
 1. A surgical instrument, comprising: a handleassembly; an actuation member disposed in mechanical cooperation withthe handle assembly; an elongated body portion extending distally fromthe handle assembly and defining a longitudinal axis, a distal portionof the elongated body portion configured to selectively engage a loadingunit; and a locking mechanism disposed in mechanical cooperation withthe actuation member, the locking mechanism configured to substantiallyprevent at least a partial movement of the actuation member when theelongated body portion is not engaged with a loading unit, the lockingmechanism comprising: a link disposed at least partially within theelongated body portion and configured for mechanical engagement with aportion of a loading unit, at least a portion of the link beinglongitudinally translatable with respect to the elongated body portion;a bushing, at least a portion of the busing disposed proximally of atleast a portion of the link, at least a portion of the bushing beinglongitudinally translatable with respect to the elongated body portion;and a connecting member, at least a portion of the connecting memberdisposed proximally of at least a portion of the bushing, the connectingmember being disposed in mechanical cooperation with the actuationmember; wherein engagement between a loading unit and the elongated bodyportion causes proximal movement of the link, proximal movement of thebushing, and proximal movement of the connecting member.
 2. The surgicalinstrument of claim 1, wherein a distal face of the bushing abuts aproximal end of the link.
 3. The surgical instrument of claim 1, whereina proximal face of the bushing abuts a distal end of the connectingmember.
 4. The surgical instrument of claim 1, further comprising acontrol rod disposed at least partially within the elongated bodyportion, wherein longitudinal translation of the control rod effects afunction of a loading unit when the loading unit is engaged with theelongated body portion.
 5. The surgical instrument of claim 4, whereinthe control rod is longitudinally translatable with respect to the link,with respect to the bushing and with respect to the connecting member.6. The surgical instrument of claim 4, wherein the control rod islongitudinally translatable through an aperture in the bushing.
 7. Thesurgical instrument of claim 4, wherein the control rod islongitudinally translatable through the connecting member.
 8. Thesurgical instrument of claim 1, wherein a transverse dimension of acontacting portion of a proximal surface of the bushing is between about2 to about 10 times larger than a distal end of a wall of the connectingtube.
 9. The surgical instrument of claim 1, wherein a transversedimension of a contacting portion of a distal surface of the bushing isbetween about 1 to about 6 times larger than a proximal end of the link.10. A surgical instrument, comprising: a handle assembly; an actuationmember disposed in mechanical cooperation with the handle assembly; anelongated body portion extending distally from the handle assembly anddefining a longitudinal axis; a loading unit including a proximal bodyportion and a tool assembly, the proximal body portion configured forselective engagement with the elongated body portion; and a lockingmechanism disposed in mechanical cooperation with the actuation member,the locking mechanism configured to enable movement of the actuationmember when the elongated body portion and the loading unit are engaged,the locking mechanism comprising: a link disposed at least partiallywithin the elongated body portion and configured for mechanicalengagement with a portion of the loading unit, at least a portion of thelink being longitudinally translatable with respect to the elongatedbody portion; a bushing, at least a portion of the busing disposedproximally of at least a portion of the link, at least a portion of thebushing being longitudinally translatable with respect to the elongatedbody portion; and a connecting member, at least a portion of theconnecting member disposed proximally of at least a portion of thebushing, the connecting member being disposed in mechanical cooperationwith the actuation member; wherein engagement between the loading unitand the elongated body portion causes proximal movement of the link,proximal movement of the bushing, and proximal movement of theconnecting member.
 11. The surgical instrument of claim 10, wherein adistal face of the bushing abuts a proximal end of the link.
 12. Thesurgical instrument of claim 10, wherein a proximal face of the bushingabuts a distal end of the connecting member.
 13. The surgical instrumentof claim 10, further comprising a control rod disposed at leastpartially within the elongated body portion, wherein longitudinaltranslation of the control rod effects a function of the loading unitwhen the loading unit is engaged with the elongated body portion. 14.The surgical instrument of claim 13, wherein the control rod islongitudinally translatable with respect to the link, with respect tothe bushing and with respect to the connecting member.
 15. The surgicalinstrument of claim 13, wherein the control rod is longitudinallytranslatable through an aperture in the bushing.
 16. The surgicalinstrument of claim 13, wherein the control rod is longitudinallytranslatable through the connecting member.
 17. The surgical instrumentof claim 10, wherein a transverse dimension of a contacting portion of aproximal surface of the bushing is between about 2 to about 5 timeslarger than a distal end of a wall of the connecting tube.
 18. Thesurgical instrument of claim 10, wherein a transverse dimension of acontacting portion of a distal surface of the bushing is between about 2to about 5 times larger than a proximal end of the link.